Table 2.

Daily Supplementation of Folic acid in the PRAM study (Connecticut, USA): month before conception through 3^rd month of pregnancy.

	Folic acid Mean (SD)	N	% of total group	Asthma at 6 years
				(n=223)	(14.9%)
Month before conception
Folic acid (mcg)	303 (367)	768	51.2	92	6.1
No use		731	48.8	131	8.7
<400		89	5.9	15	1
400-800		625	41.7	70	4.7
>800		54	3.6	7	0.5
First month of pregnancy
Folic acid (mcg)	402 (402)	913	60.9	112	7.5
No use		586	39.1	111	7.4
<400		87	5.8	16	1.1
400-800		746	49.8	86	5.7
>800		80	5.3	10	0.7
Second month of pregnancy
Folic acid (mcg)	605 (390)	1218	81.3	174	11.6
No use		281	18.8	49	3.3
<400		92	6.1	11	0.7
400-800		1009	67.3	152	10.1
>800		117	7.8	11	0.7
Third month of pregnancy
Folic acid (mcg)	676 (349)	1288	88.4	187	12.5
No use		191	12.7	36	2.4
<400		69	4.6	11	0.7
400-800		1144	76.3	165	11
>800		95	6.3	11	0.7
First trimester
Folic acid (mcg)	497 (301)	1381	92.1	202	13.5
No		118	7.9	21	1.4
<400		342	22.8	65	4.3
400-800		953	63.6	130	8.7
>800		86	5.7	7	0.1